Man page 9 : try_to_release_page

try_to_release_page - release old fs-specific metadata on a page

int try_to_release_page(struct page *  page , gfp_t  gfp_mask );

page
    the page which the kernel is trying to free

gfp_mask
    memory allocation flags (and I/O mode)

The address_space is to try to release any data against the page (presumably at page->private). If the release was successful, return `1Aq. Otherwise return zero.

This may also be called if PG_fscache is set on a page, indicating that the page is known to the local caching routines.

The gfp_mask argument specifies whether I/O may be performed to release this page (__GFP_IO), and whether the call may block (__GFP_WAIT & __GFP_FS).